OLYMPIA - Puget Sound's resident orcas should be added to Washington state's endangered species list because the marine mammals are at critically low levels and are vulnerable to several continuing threats, according to a recently completed status report by the Washington Department of Fish and Wildlife (WDFW).

The department is accepting public comment through April 1 on the status report and recommendation that the orcas, also known as killer whales, be included on the state's list.

The Washington Fish and Wildlife Commission, the nine-member citizens' panel that sets policy for WDFW, is expected to take action on the orca-listing proposal at its April 2-3 meeting in Spokane.

Written comments on the final report and listing recommendation must be submitted no later than April 1 to Harriet Allen, Wildlife Program, WDFW, 600 Capitol Way N., Olympia, WA., 98501-1091. Comments can also be sent to WDFW by e-mail, at wildthing@dfw.wa.gov.

The state listing process is separate from the federal process, and carries limited state authority that is confined to the malicious harassment or killing of a state-listed endangered species. A state listing would trigger the development of Washington's own recovery plan, which would serve to guide efforts to protect the orcas.

The recovery plan would be done in concert with the actions of U.S. and Canadian federal agencies that have management authority for marine mammals.

The state designates as "endangered" those species native to Washington that are seriously threatened with extinction throughout all or a significant portion of their range within the state.

The status report is the latest product of an ongoing effort by Washington state, federal and Canadian officials to assess the health of the region's resident orca population.

Canadian officials have already listed the southern resident orcas as an endangered species. The U.S. government, which designated the southern resident population as a "depleted stock" under the national Marine Mammal Protection Act, is currently reviewing its decision to not list the orcas under the federal Endangered Species Act (ESA).

WDFW's status report was funded in part by a $100,000 appropriation from Gov. Gary Locke as part of the governor's larger initiative to strengthen the health of the Puget Sound ecosystem and the fish and wildlife species that depend on it.

"The solid scientific work reflected in this report gives us an excellent base on which to assess the health of our resident orca population and determine what the next steps should be to protect one of the most enduring symbols of Puget Sound and the Pacific Northwest," said WDFW Director Jeff Koenings.

The Puget Sound resident orca population consists of three social groups, identified as the J, K and L pods. Southern resident orcas primarily feed on salmon and other fish. They are most often seen in Puget Sound from late spring to fall.

The southern residents' population has declined by 18 percent since 1995, according to the status report. The L pod, which makes up about half of the southern resident population, has seen both higher mortality and lower birth rates, particularly in the past decade.

The status report cites several possible factors that could be responsible for the orcas' decline, including an overall decline in salmon numbers throughout the region, as represented in the federal listing of salmon under the federal ESA, accumulations of long-lived pollutants such as PCBs and DDT, and possible harassment from "whale-watchers" and other marine vessels.

"The state's roles and responsibilities would complement, not replace, those of the federal agencies," Koenings added. "We want to operate from a clear understanding of the science so as to not duplicate the federal recovery plan."

Transient orcas also inhabit state waters intermittently throughout the year, though they differ from the resident pods in their smaller social groups and preference for marine mammals as a prey base. Two additional orca populations, offshore and northern residents, rarely venture in state waters.